High-rise building made of CLT increases significantly its own weight. Therefore, the collapse of the wall bottom is concerned. Main purpose of this study is to verify the effect of the reinforcement with screws for avoiding the collapse of the CLT wall bottom by extreme vertical load. Test pieces of CLT wall bottom were reinforced by screws. As a result, we got better structural result with screw reinforcement than without screw. From these experimental results, the reinforcement of CLT wall bottom using screw at perpendicular angle to the fiber direction is effective in workability because it does not need seat-dig hole.
Conventionally, energy absorption of joints in wooden structure has been obtained by yield deformation of steel parts. However, we have tried to control behaviour such as rigidity type or ductility type with combinations of wood fibre direction using screws in wooden structure for joint design. We defined the combination ratio of wood fiber as Rp (Ratio of parallel). First, we used special large diameter bolts to get high rigidity and ductility with embedding into combinations of parallel and orthogonal fiber directions. Then, we used long-screw which are more common in the market. We made all CLT test pieces by ourselves. We have compared the joint behavior with experiments and analysis. As a conclusion, we got following results of this study. When Rp rises, rigidity will be higher. On the other hand, ductility will be higher when Rp falls. We suggest the relationship equation for Rp and the rigidity and ductility of the increase or decrease by the theoretical value.
Study on Seismic Performance of Building Construction with Cross Laminated Timber: Part 14: Deformation of Joints and Fracture Behavior on Three Story Full-Scale Static Load Test
This paper gives a bibliographical review of the finite element methods (FEMs) applied in the analysis of wood. The added bibliography at the end of this article contains 300 references to papers and conference proceedings on the subject that were published between 1995 and 2004. The following topics are included: Wood as a construction material—material and mechanical properties; wood joining and fastening; fracture mechanics problems; drying process, thermal properties; other topics. Wood products and structures—lumber; glulam, panels, wood composites; trusses and frames; floors, roofs; bridges; other products/structures.
Innovative steel - Cross Laminated Timber (CLT) connections are key elements in developing hybrid steeltimber composite floors with desirable strength and serviceability performance. The performance of floors mainly relies on the load-slip behavior of connections for composite action. The long-term behavior of timber is mainly affected by elastic and mechano-sorptive creep, resulting in a different total slip than the initially observed one. In this study, the long-term load-slip behavior of two different types of connections with pre-tensioned high-strength bolts and dog screws are experimentally assessed at two different stress levels. Furthermore, the effect of grain orientation on the results is studied by considering specimens with parallel and perpendicular grain orientations under sustained loads. Load-slip curves show a stable performance of a composite action over time. Furthermore, an analytical model is fitted to the loadslip vs time data which can be used to predict long-term behavior of floors in future.
Innovative steel - Cross Laminated Timber (CLT) connections are key elements in developing hybrid steeltimber composite floors with desirable strength and serviceability performance. The performance of floors mainly relies on the load-slip behavior of connections for composite action. The long-term behavior of timber is mainly affected by elastic and mechano-sorptive creep, resulting in a different total slip than the initially observed one. In this study, the long-term load-slip behavior of two different types of connections with pre-tensioned high-strength bolts and dog screws are experimentally assessed at two different stress levels. Furthermore, the effect of grain orientation on the results is studied by considering specimens with parallel and perpendicular grain orientations under sustained loads. Load-slip curves show a stable performance of a composite action over time. Furthermore, an analytical model is fitted to the loadslip vs time data which can be used to predict long-term behavior of floors in future.
